Conventionally, an ejector refrigeration cycle is known to be a vapor compression refrigeration cycle device including an ejector.
In this kind of ejector refrigeration cycle, a refrigerant flowing out of an evaporator is drawn into a refrigerant suction port of an ejector by a suction effect of a high-speed injection refrigerant injected from a nozzle of the ejector. A mixed refrigerant of the injection refrigerant and the suction refrigerant is pressurized by a diffuser (pressurizing portion) of the ejector. Then, the mixed refrigerant pressurized by the diffuser is drawn into a compressor.
Thus, the ejector refrigeration cycle can reduce the power consumption in the compressor, thereby improving a coefficient of performance (COP) of the cycle, compared to a standard refrigeration cycle device in which a refrigerant evaporation pressure in an evaporator is substantially equal to a suction refrigerant pressure in a compressor.
Patent Document 1 discloses the structure of this kind of ejector refrigeration cycle that includes two evaporators. The ejector refrigeration cycle allows a refrigerant to flow out of one evaporator (first evaporator) into a nozzle portion of the ejector, while drawing a refrigerant flowing out of the other evaporator (second evaporator) into a refrigerant suction port of the ejector.
In the ejector refrigeration cycle described in Patent Document 1, the first evaporator and the second evaporator have different ranges of refrigerant evaporation temperature. In the technique of Patent Document 1, the ejector refrigeration cycle is applied to a cold-storage device. The first and second evaporators are arranged in different cold-storage chambers (spaces to be cooled) and designed to be capable of keeping the respective cold-storage chambers cool in different temperature ranges.